1. Field
Example embodiments of the following description relate to an electrical instrument, a power management apparatus, a power management system having the same, and a method for controlling the same to adjust power consumption, thereby balancing supply with demand of power.
2. Description of the Related Art
With the development of information and communication technologies, the number of devices powered by electricity is rapidly increasing, and thus, power demand increases year by year. In a power demand pattern, peak capacity is not reached during most days of the year, that is to say, power plants only operate at full capacity during a few days out of the year.
A state in which a high power demand is required for a short time is called peak load. Costs for constructing an additional power plant for peak load are extremely high and maintenance costs for power plants constructed to maintain peak load for a short period are considerable.
Recently, numerous developers are conducting intensive research into a demand management method for temporarily restricting power consumption by limiting peak load without constructing such additional power plants. For the aforementioned purposes, demand management is a focus of attention, and a great deal of research is focused upon an advanced demand management format for demand response (DR).
DR is a system for intelligently managing energy consumption depending upon variation in power rates. That is, a consumer uses power in response to power rates rather than according to an ordinary power consumption pattern.
According to DR, a power provider can induce users to consume power in a low power rate period, and restrain users from consuming power in a high power rate period, and thus, users can use power at a low rate.
Therefore, electrical instruments to which DR is applied have been developed. The electrical instruments are provided with real-time power rates from a power provider and are on/off controlled based on the power rates.
However, conventional electrical instruments to which DR is applied cannot efficiently execute functions that users desire because they are powered on/off based on power rates.